State Municipal Assistance for Response and Transition Act or the SMART Act This bill provides $500 billion for a Coronavirus Local Community Stabilization Fund to address the economic effects of the COVID-19 (i.e., coronavirus disease 2019) pandemic on state, local, and tribal budgets. The bill also expands the uses of payments from the Coronavirus Relief Fund. The bill allows a jurisdiction to use funding from the Coronavirus Local Community Stabilization Fund or Coronavirus Relief Fund for (1) necessary expenditures related to COVID-19 that were not accounted for in the jurisdiction's budget, including the nonfederal share contribution requirement for disaster or emergency assistance; or (2) expenditures the jurisdiction would otherwise be unable to make because of decreased or delayed revenues. Funding from the Coronavirus Local Community Stabilization Fund may be used for expenditures through 2022. The bill (1) reserves specified funds for payments to tribal governments; (2) apportions funds to states based on population, infected population, and revenue lost; (3) provides for payments to counties and municipalities based on lost revenue. The bill conditions funding on each state agreeing to fair and equitable budgeting based on need. The Office of Inspector General of the Department of the Treasury may use amounts appropriated to carry out oversight and recoupment activities under this bill.